Inspired as usual by this group, I just cooked up an ounce or so of the gunpowder, a disappointing tea from a fairly famous local vendor that has been sitting around (airtight) for a year or so. I used a small stainless-steel pan, preheated on an electric stove to burn off any residues. Poured in the tea, stirred almost constantly to keep things even. A white vapor was emitted continuously during the two minutes or so that I cooked it; perhaps that was mostly caffeine. (I let a little condense on a cold spoon and tasted it, but couldn't be sure.)
Smell was wonderful. The resulting leaf smelled a little smoky - nothing like a Lapsang - and made a brownish brew. Much better than the original on all four steeps: less astringent, and not much less green-tea flavor (perhaps because there hadn't been much to start).
Now I'd like to try a highly fermented but low-roasted oolong. Might be a good way to get a fresher tea experience at moderate cost. Any recommendations?
-DM